taskbar disappears..

[Gracie]

hello folks. I have just reformatted a lady's computer and given it back  and am satisfied that the machine was behaving as it should during the time it was here.

Tonight though she has phoned me to say that she left the computer on while she did something else, and when she came back and 'woke it up' the desktop icons were larger and the taskbar was not visible.

That did not happen here, and it did not happen with her previous to the reformat, so what could be causing  it now I wonder?

I put Outlook on and Plus! and AVG 7.0 and Tiny Firewall , those apart there is nothing that she didn't have on before. Any Ideas what could be causing this please?

[query]

Is it possible the user modified the desktop settings by clicking in the wrong place?

[Gracie]

it is possible I spose, but her story is that she was in Outlook Express  doing her e-mail ( she had about fifty to catch up on) and  decided she wanted a break from that so went off, leaving the computer still running ( she didn't say  whether she shut down OE first) and when she came back to resume and woke it up, she  saw the desktop looked as if the icons were larger ( as if the resolution had changed) and the taskbar had disappeared, so she could not shut the machine down.

I  tried to get her to change the screen size but it didn't go too well - I think she was  in a bit of a panic.

Thing is, if the computer had locked up, she wouldn't have seen any icons or been able to move the cursor would she?

It  seemed to me that the display resolution had possibly defaulted to  640x480 or whatever the lowest is ( Dell monitor) and that the taskbar was hidden but still present.

I should have asked her to  do Ctrl-Esc or the three keys, but I didn't , silly me. After pushing the reset button  it was all back to normal, so immediate crisis over - but I would like to understand what  happened so I can prevent it from occurring again.

Thank you for answering Q :)

[scuzzy]

It is possible that "Windows" happened. If a restart resolved the problem, and it does not reoccur, I wouldn't concern myself with it. On the other hand, it could be a video driver problem. If the problem comes back, that would be a good place to start. If you are confident that it's not the video driver, then reseating the video card and inspecting the cables would be a good idea.

[Buffalo2102]

What kind of screensaver is running (if any).  Is it a default Windows jobby?  Or is it set to hibernate after a while?

It is possible that the resolution changed when the screensaver was deactivated and I would agree with Scuzzy and check out the video drivers.

[Gracie]

there might have been a Themes screensaver running.
There was when I  first had it as well and I put the same theme on when I reformatted.

Why would it  start causing problems now I wonder.

This might be relevant though. When I first connected the machine back to her monitor (Dell) and booted up, the monitor  kept  switching off and restarting until I had got to the place where windows puts a default driver on. After that it was fine.  
The BIOS is  Dell also (machine is Dimension V333C) and I noticed it was set to non-plug and play. Would that make a difference?

It's power saving is the default config - I did not  alter that.

The video drivers were the last that were available for the ATI Rage Pro  -  I got them off the Dell site. It is a chip not a card. Would that  make a difference?

thank you for your help  chaps :)